If you’re into road cycling, as I am, you can enjoy it your whole life without ever entering a race. The same applies to mountain biking. On the other hand, cyclocross is pretty much all about racing — and yet the sport’s laid-back atmosphere is a huge part of its growing appeal.

I experienced that atmosphere firsthand recently at a cyclocross event held on the fields of the Armed Forces Retirement Home in the District. What I found was something like a really big family picnic in the park, with a steady stream of races providing opportunities to break a sweat before cracking open a beer.

As one longtime participant said, “This is faster [than mountain biking]. It’s way more social — there’s a party going on with a bike race nearby.”

Cyclocross, or “cross,” as many practitioners call it, is indeed something of a cross between the two better-known forms of cycling. Its arboreal setting calls to mind mountain biking, but it’s more about keeping up a steady pace over rolling (and sometimes muddy) hills, and the bikes themselves look much more like their road cousins.

The iconic distinction of cyclocross is that competitors are occasionally forced to sling their bikes over their shoulders and run across certain sections. I was told a classic line about the sport: “It’s like steeplechase, but you carry the horse.”

The origins of cyclocross are somewhat murky, but it’s believed to have originated in the late 1800s with Northern European cyclists looking for ways to stay fit and have fun after the summer racing season ended. The sport is popular in France and the Netherlands, and it is huge in Belgium, which we can thank for the delightful tradition of enjoying beer and french fries at events.

For Svetlana Mack, a 17-year-old from Silver Spring who has already spent years competing in various forms of cycling, cyclocross is her favorite, because “it’s less, like, focused and serious.” (Good to know that, for her, it’s not about the beer.)

“This is the best sport to start with,” Mack said. “Because you have to learn all the technical skills, and then when you get on the road, you have all the bumping and turning, and it’s just safer if you start with cyclocross.”

It’s easy to see how someone who hadn’t raced on a bike before would be more inspired to do so while attending a cyclocross race than a road race. The latter can seem intimidating, if not terrifying, with a large group of riders whizzing by in tight formation on an unforgiving surface. Getting dropped from that formation (better known as the peloton) and spending the rest of a road race in a depressing, solitary struggle can also be an unappealing prospect for newbies.

Contrast that with cyclocross, where competitors are spaced more evenly along a less-speedy course — allowing for individual battles among those with little chance of finishing on the podium — and spills usually take them into grass or mud. There’s “much less skin lost in cross,” the aforementioned longtime participant, Becky Frederick, said with a chuckle.

One of the organizers of the event I attended, Bill Schieken, told me that cyclocross is “really an entry point into the sport, and the interesting demographic that we also see is masters, guys in their 40s, that are doing cycling for the first time. And they don’t want to go on the road, they don’t want to crash and be out of work . . . so they get into cyclocross, and that’s where they’re starting.”

Schieken, 46, who runs the cyclocross Web site In the Crosshairs (www.cxhairs.com) and does a podcast and videos focusing on the sport, noted its “party atmosphere” but made sure to emphasize that races are no joke.

“You have to be prepared for anywhere from 40 minutes, in the lower categories, to an hour of all-out effort,” Schieken said. “All-out, with bursts throughout, so you have to have a high level of fitness, you have to have that high-end, VO2-max training, where you’re able to do burst-recover-burst-recover.”

Schieken added: “If you do a race correctly, it hurts. It hurts a lot.”

The sport has grown rapidly in recent years in the United States, according to Colin Reuter, who created Cross Results (www.crossresults.com), an online database of races spanning 2006-2015, and works for BikeReg, which provides online registration for thousands of cycling events.

Reuter told me, via e-mail, that his database recorded a 27 percent increase in unique racers from 2010 (25,537) to 2014 (32,619). In the Mid-Atlantic region, the number of cyclocross participants more than doubled from 2008 (2,345) to 2014 (4,882).

It is possible to just go out and do some ad-hoc cyclocross, much as one might hit the road or a mountain-bike trail, but the essence of the sport is navigating a course, so you would still want to, say, set up some barriers in a field. Participants certainly benefit from gaining greater expertise in techniques such as dismounting smoothly and taking corners at speed, and they often seek out or create their own practice courses.

Before cyclocross season starts (it usually goes from September into December), many riders train on roads, ramping up the intensity of their intervals, according to Schieken. It is also worth doing some running, as there are bursts of that, and hitting some mountain-bike trails, which can be accomplished in the absence of any particular setup.

“Without the tape here, it would just look really silly if one person went out and rode around — you would never do that,” Craig Etheridge, a 35-year-old from Baltimore who won the single-speed race at the D.C. event, said. “So really, the cool thing about it is that the race can only exist at the race — you can go out and practice, but it’s just sort of silly.”

Etheridge said he started racing on a road bike, using the fattest tires he could find, but Schieken said mountain bikes work much better for beginners who don’t want to invest in a cyclocross-specific bike right away. Personally, I may well buy one soon, partly because I am looking for a new commuter vehicle, and while I have always gone with road bikes in the past, I am tempted to sacrifice some speed for the rugged versatility cross bikes offer.

Of course, the best reason to get a cyclocross bike would be that I would then have almost no excuse for not signing up for a race. As it is, I already have little excuse, now that I’ve seen how much fun they look.

@desbieler on Twitter

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